Pokemon Ultimate Mystery Dungeon
by fuji-rakki
Summary: Riku is an ordinary Riolu, aside from the fact that he's a Guild-Master Rank detective (or the pokemon equivalent of an Ultimate talent). He definitely didn't expect to be accepted into Hope's Peak, a prestigious guild for only the top explorers, or for it to be hijacked by an insane Teddiursa with a thirst for blood. Danganronpa but with Pokemon, this will be quite the trainwreck.
1. Prologue and Chapter 1: Daily Life

**A/N I'm so sorry for any typos or misspellings! I wrote this very late at night and I have not been taking my medications. Those of you who know me know that I tend to type and speak before I actually know what I'm going to say. A few things before we start though:**

 **The way this is written, some sentences and dialogue will be spaced out a bit differently than your typical paragraph to make it easier for me to read and write. I hope this doesn't bother you that much.**

 **All of these are OC's preestablished in their own respective universes, but I've put them all together for the sake of this fanfic (i.e Izumi, Murasaki and Riku all knew each other in their own story, but here they're just meeting.)**

 **This is a crossover with Danganronpa and combines the lingo used in PMD with that of DR (for instance Ultimates/SHSLs in this universe are referred to as 'Guild-Master Ranks', and Hope's Peak Academy is actually an explorer's guild. The characters are still referred to as students most of the time.)**

 **This was also posted on google+ and will probably be posted on Ao3, so if you see them there then that will be me.**

 **The rating may change as well in future chapters, especially once we start the killing. Just so you know.**

 **With that out of the way, I hope that you enjoy~**

 **-Wisteria**

* * *

Riku was asleep, wrapped in a calming and heavy blanket of warm unconscious  
Or rather, he had been knocked out and dragged off to an unfamiliar place.

When he woke up, the first thing that he noticed was that it was pitch-dark, and he could barely even see his paw in front of his face. Walls pressed in around him, and his sensors immediately flared out to look for signs of life. Nothing. He sighed and pulled his coat tighter around himself, before pushing out an arm. He realized that the wall in front of him was actually a door. He pushed it open and stumbled out into a lit classroom. He blinked repeatedly, forcing himself to get used to the light. He looked around, turning back to the door to find it led to a supply closet. On the door was a note:

 _Hello! Welcome to the prestigious Hope's Peak Guild. Please make your way to the training field at 8AM for your orientation._

 _O-Orientation!?_ he blinked in surprise, then looked at a clocked that was on the wall. It read 8:15.  
 _Dammit, I'm late!_ Immediately Riku bolted for the door leading out of the classroom, throwing it open and darting through the halls.

Miraculously he went the right direction despite his rushing, because he made it to a door labeled "EXIT" in large red letters. He opened it and immediately sunlight flooded through, blinding him. Riku let out a grunt of surprise and annoyance. He stepped through, and his gaze was met with an open field. Fifteen other Pokémon were there, talking and mingling amongst themselves. He looked around, catching his breath.

"Hey! You're late!" Riku whipped around to stare at the owner of the voice. Standing before him was another Riolu. Unlike him, this one was not wearing anything and his fur was a rich golden color. His eyes were red and, as opposed to Riku's soft amber gaze, burned with a fierce determination. "You know that won't be tolerated here!" He barked.

"Hey man, lay off." Came another, more relaxed voice. Next to him was a Charmeleon, his burning tail wrapped neatly around his feet. He wore a pair of goggles, as well as fingerless gloves and a soot covered leather band around his tail. His face was dirty and soot covered, and his talons were calloused and tough looking. But despite his hard appearance, his gaze was warm and friendly.

"U-Um...hi? Do either of you know what's going on right now?" Riku looked between them, messing with his trenchcoat out of nervousness.

"No, I'm just as clueless as you are." The Charmeleon shook his head. "I woke up in a supply closet in one of the classrooms, and there was a note telling me to be here."

"Hey, the same thing happened to me." Riku's eyes lit up.

"Maybe this is some sort of weird ARG," a sunshine yellow Vulpix suggested. "I bet it's some weird ritual they do as part of the orientation." She had soft brown eyes but unlike the Charmeleon, her gaze was narrow and fierce, and held some degree of aggressive playfulness. Her six tails were swept around her legs protectively and her eyes surveyed the rest of the group, observing them with caution.

"I doubt it." A Leafeon that was next to the Vulpix shook her head. She wore a tattered cloak around her and was visibly shaken, eyeing the other Pokémon nervously, as if afraid they might suddenly attack.

"Someone had better tell me what's going on right now, dammit!" A Flygon roared. "Or I'ma have to get rough!" She had a purple scarf and fingerless gloves, and the highlights of her wings were a deep lilac. She naturally towered over the rest of the students and had an air of aggressive arrogance and fierce determination about her. Her aura overpowered Riku's senses and he had to shake his head quickly out to prevent from getting dizzy.

"...Oh, I see everyone has gathered!" A high pitched voice suddenly rang out. "There, there. You all must be _so_ confused! Don't worry, I'll be sure to clear everything up for you lickety split~" it dripped with a sickening soothing sweetness that was clearly very fake, and on the judge's podium a monochrome Teddiursa suddenly appeared. Half of the bear's body was black, the other white, and its black half had a jagged red eye that pierced the souls of every Pokémon gathered there.

"Wh-Who are y-you?" A small, white Eevee whimpered. The poor thing was crouched low to the ground, shivering. Their ears were tipped with grey and they had a light gray collar of fur. Their tail was also tipped with gray and their eyes were fully black. The Eevee was, by basic definition, very bland and forgettable. Even their markings weren't that notable. "Y-You're not going t-to kill us, a-are you?"

"Kill you? Now, why would I ever _dream_ of killing my dear students?" The Teddiursa giggled. Its teeth were razor sharp. "No, that's for you all to do yourselves." It checked its claws on one paw.

"Answer the kid's question. Tell us who you are!" The Vulpix yelled. Though she didn't match the Flygon in stature, she clearly went above and beyond in spirit.

"Why, I'm Monokuma! Your proud guildmaster. Like you, what I lack in size, I make up for in strength and charisma." The Teddiursa, whose name was apparently Monokuma, stated proudly.

"Guildmaster? You mean, of this place?" A Mienfoo piped up, tilting her head.

"Yes! Of the Guild you will all spend the rest of your lives in~"

"Wh-What!?" The golden Riolu from before jumped. "You can't possibly be serious, r-right!?"

"I-I don't want to be stuck here! N-Not with these l-losers..." a haunched over Espeon with a shifty gaze muttered.

"You heard me! You're going to be staying here for the rest of your lives. But of course, there is one way you can get out..." Monokuma repeated as he flashed another grin. This one was completely void of any warmth, instead thinly masking a twisted, morbid excitement.

"And what would that be?" The Leafeon stood up, hiding her shakiness. She was bold despite her obvious fear.

"Why, killing of course! What, ya didn't hear the hint I dropped earlier? Upupupupu~" the Teddiursa tittered.

"K-K-Killing!?" The Eevee from before looking even more terrified now, tears pooling in the corners of his dark eyes.

"You heard me!" The bear cub did a back flip off the podium, landing perfectly. He brushed himself off and bowed dramatically. "In order to leave you must kill one of your fellow explorers! However, the one catch is that you must not get caught! If you do, you get punished." He grinned wickedly, exposing his claws. "Understood? If so, then get lost and get plotting!"

"Wait!" A slightly curvy freckled Totodile stepped forward, her brow furrowed in confusion. "You're just suddenly plunging us all into this, without any explanation! Do you at least have a reason?"

Monokuma shrugged. "Maybe I do, but it wouldn't be any fun if I told you~" with that, he vanished into thin air, leaving the Totodile to reach at thin air. She shook her head and sighed. Immediately the group started buzzing with activity, some excited, some terrified. Whatever was going to happen, Riku knew it would only spell trouble for himself.

* * *

Steeling himself, Riku went over to a group of his fellow classmates, deciding to introduce himself. He started with a nervous looking Shinx who hadn't spoken throughout the entire orientation. His gaze darted around, and though he didn't looked distrustful, he was wary. He jumped as he noticed Riku approached. "N-Nyah! You aren't going to kill me, a-are you?"

Riku frowned, before shaking his head. "No way. Besides, I'd obviously get caught." He drew in a sharp breath as the last sentence only made the Shinx look even more tense. "Look, I don't plan on killing anyone, even if it does mean I have to stay here for the rest of my life. Can you at least tell me your name?"

"I-I'm Max." The Shinx answered timidly. He bit his lip and glanced away. "Underwhelming, I know."

"No, no. Keep going!" Riku gently urged him onwards.

"I-I'm the Guild-Master Rank Electrokinetic. It's not really anything special...but I'm happy to meet you." Max offered a nervous smile.

"I'm pleased to meet you too, Max. I'm Riku, the Guild-Master Rank detective." The Riolu held out a paw and Max shook it. "Th-That wasn't so bad..." the Shinx breathed out after pulling away. "I-I'm going to go find Astra." With that, he scuttled away in the direction of the yellow Vulpix from before.

Next, Riku turned his attention to the Charmeleon. The lizard gave him an easy smile. "Well, this is quite an interesting development."

"You're...not worried at all?" Riku asked. "Not even a little? Don't you want to survive?"

"Well, of course I do. But freaking out of it isn't going to help anything." The Charmeleon shrugged. "Besides, I've been in worse situations."

 _What could possibly be worse than being forced to kill for freedom?_  
Riku decided not to pry. "So, what's your name?"

"I'm Taiki, the Guild-Master Rank blacksmith. I'm quite handy with metals. If you ever want armor made, I'm the go-to guy." Taiki chuckled, tail flicking lightly. He was much more easygoing and friendlier than most Charmeleon Riku had spoken to. Perhaps it had something to do with how he was bought up?

The next person Riku talked to was the Flygon. She was less enraged than before but her tail still flicked with obvious annoyance as she pawed the ground, nostrils flaring.

"H-Hi—"

"What do you want?" She promptly interrupted him, sounding tired. "If you must know, I'm Murasaki, the Guild-Master Rank daredevil. I'm not in the mood to talk right now so kindly piss off, please."

Riku flinched and walked away, hands over his head. _Well at least she was polite about it..._ he thought, disgruntled. Riku then made his way over to the scared white Eevee, kneeling down to his level.

"Hi there." He tried to offer them a friendly smile.

"H-Hi..." he responded in a small voice. The poor Eevee was shaking like a leaf, and despite his odd appearance, Riku was strongly tempted to take them up in his arms. "I-I'm Dot, th-the Guild-Master Rank E-Experiment." He flinched and cringed, instinctively waiting for the teasing to start. It didn't. Riku frowned. It was an odd specialty but he decided not to question it. "I'm Riku..." he introduced himself, further assuring the tiny Eevee that he wasn't going to bully him.

Riku then went up to the Vulpix, who was chatting away with the Totodile from before, Max cowering between her tails.

"Huh? Oh, hey beefcake." The Vulpix gave Riku a cheeky smile. He decided to ignore the nickname. "So who might you be?" he decided to ask instead of saying anything about it.

"Oh yeah, I'm Astra, the Guild-Master Rank Pyrokinetic. And don't you forget it!" She warned. "I can summon entire firestorms if I wanted to."

"Astra, you did that once and were in a coma for three whole days afterwards. Stop trying to scare the guy." Max replied pointedly,  
voice muffled by her tails.

"Aww, I'm just having a bit of fun." She looked crestfallen, but brightened up quickly and grabbing the Totodile's arm as she tried slinking away. "But you gotta check this out! This girl's a seer!"

"Y-Yeah, that's kind of my specialty." The Totodile answered in exasperation, tugging her arm away. "I'm Crystal, the Guild-Master Rank seer." She shrugged. "Make of that what you will."

Just as Riku was about to go over to the Riolu, an interesting sight caught his eye. A dark brown Smeargle with mismatched blue and green eyes was chasing the shady Espeon from before.

"Come on, show me your cool sacrificial knife! Summon a demon! Draw a pentagram in the sand. At least do _something_ cult-y!" The Smeargle shouted, leaving a trail of paint as she went.

"No! L-Leave me alone!" The Espeon cried out, running and hiding behind Riku who let out a grunt of surprise.

"Heyyyy, no fair." The Smeargle slowed and puffed out her cheeks. "You can't hide!"

"Sh-Shut up..." the Espeon lashed her tail in agitation.

"U-Uh, what's going on?" Riku blinked in confusion.

"Oh, I was just trying to get this girl to show me her cool cult things!"

"I told you, I don't have any 'cool cult things'," The Espeon retorted. "Just my knife. A-And there's no way I'd ever let the likes of you get your filthy paws on it!"

The Smeargle looked crestfallen. "Aw, you're no fun." Her eyes brightened at the sight of Riku. "Oh, hiii! I'm Nutmeg, the Guild-Master Rank medium! I can talk to ghosts! Isn't that cool? You think that's cool, right?" She was just inches away from Riku, and the poor Riolu boy leaned back against the Espeon.

"H-Hey! Get away from meeee!" She flailed wildly, and they both fell down. "I-I'm Vasily! The Guild-Master Rank Cultist! Now please, leave me alone!" She scampered out from under Riku, bounding away. Immediately Nutmeg charged after her. "Wait! I haven't seen your knife yet!"

"Ghosts..? Wait, cultist!?" Riku picked himself up, brushing off and blinking with confusion. "How is that a specialty?" He shook his head, before making his way over to the rest of the students.

* * *

The next person he introduced himself to was the Leafeon. She flinched as he came up to her.

"Wh-Who are you?"

"I'm Riku, the Guild-Master Rank detective. You?"

"R-Remy. Guild-Master Rank Assassin." She sighed. "But I promise, I'm NOT plotting to kill any of you. So many people have asked me that today."

Riku hid his amusement. "I didn't think you were." Truth be told, Remy didn't look dangerous at all. In fact, Riku doubted she'd even survive.

He decided to let that thought go unspoken.

Riku made his way over to the other Riolu, who was now talking to the Mienfoo from before.

"Hi," he walked over to them.

"Oh! Hiii~" the Mienfoo waved energetically. She appeared cheerful despite their situation. "I'm Svetlana, the Guild-Master Rank martial artist! But you can just call me Svet." Her tail was wagging violently. She has had a slight, undecipherable accent...weird.

"And I'm Nico, the Guild-Master Rank explorer! I think we met already?" The Riolu put a paw behind his head. "Sorry for getting on your case earlier, by the way. I take Guild regulations very seriously. Ending up in a place like this has always been a dream of mine..." he sighed. "I just wish it didn't go down like _this_."

"I-It's no problem! I was just caught off guard...And, I feel the same way." Riku turned his head and coughed awkwardly. As he did so, a flash of green caught his eye. Standing off from the others was a Treecko. She appeared to be partially evolved, with a leaf sprouting from her head and budding from her elbows. She had a soft yellow gaze and her scales were pale with agitation. He made his way over to her.

"I—"

"I-Izumi. Guild-Master Rank mediator. P-Pleased to make your acquaintance." The Treecko spouted off before Riku could even get a word out.

"Oh. Um, I'm Riku. Guild-Master Rank detective. Why aren't you talking to the others?"

Izumi shifted her eyes away, but her scales betrayed her emotions, muddled brown with fear. "N-No reason. I just prefer to keep to myself, is all." She let out a breath. "I'm feeling a little nervous. There are a lot of Pokémon here..."

Riku nodded in understanding. He wanted to put a paw on her shoulder, but she didn't look like she wanted to be touched. He decided to try later. Instead he went over to a Lopunny, who was observing the others with mild contempt in her gaze.

He didn't even have to say anything.

"Holly, I don't remember my specialty. Leave me alone." She growled at him, piercing dark gaze penetrating his own.

"I— okay..." Riku shuffled away, not wanting to risk angering her further.

He then went to speak to a red Absol who had been sitting quietly, calmly observing the others.

"H-Hi—" he started. At this point Riku wouldn't even be surprised if the Absol chose to ignore him altogether. However, she didn't, instead turning to him with a small reserved smile.

"Oh, hello. My name is Pandora, I'm the Guild-Master Rank treasure hunter." Her voice was a calm purr, and her aura was lax but resolute. "Quite a dangerous situation we're in, but I don't mind at all. I love danger." She chuckled.

 _Okay, so she isn't normal either. I should've expected that._ he sighed inwardly, deciding to turn to the next Pokémon, a Pachirisu wearing a red scarf.

"Hi! I'm Zephyr, call me the Guild-Master Rank technician!" He put his paws on his hips. "Believe me, I'm stronger than I look!"

"I- oh." Riku frowned slightly.

"Yep! I'm pretty handy with all kinds of mech. I've been trying to develop technology that will greatly boost your speed in dungeons." He stated proudly, puffing his chest out.

Riku thought that was interesting, but things like like mechanics didn't particularly tickle his fancy. He noticed that the other Pokémon had started to disperse, heading back into the Guild. Riku followed, unsure of what else to do. This strange bunch of Pokemon were his crewmates now, whether he liked it or not, and it was something he'd just have to get used to.


	2. Chapter 1: Daily Life part 2

**Okay so, like I said, this has been posted elsewhere beforehand so I already have the first few chapters done.**

 **This will also have a pacing similar to the anime, so the murder might happen in this chapter or the next one. I expect this will have about 20 chapters? Possibly less since I'm condensing the parts.**

 **WIth that out of the way, I hope you enjoy~**

 **-Wisteria**

* * *

 **Those who Live and Those who let Live, Chapter 1: daily life**

Riku eventually found himself in a canteen type place. Sitting at the table were Murasaki, Taiki, Vasily, Holly, Dot, Nutmeg, Remy and Max.

"So what's happening?" He asked uncertainly.

"We're trying to find a way out," Holly told him. "No luck yet."

"I checked the kitchen and didn't find anything, but there was a ton of food," Max added. "I doubt we'll starve."

"What makes you say that? It probably won't feed a bunch of guild 'mon for more than a month." Remy pointed out.

"A-Actually, Monokuma popped up to me while I was in there." Max replied, shaking his head.

"You mean he just appeared in front of you?"

"Yeah! He said that the budget is otherworldly and that we won't go hungry at all."

"How do we know he's not lying?" Holly raised a brow. "For all we know he's thinking of **starving** us."

"I doubt that's the case..."

More Pokémon had begun to file into the canteen at this point, reporting their findings. Most of them found nothing.

"It looks like there are enough rooms for all of us," Astra said. "Which means I don't have to sleep with the boys!" She stretched, looking pleased with herself.

"Really? I didn't expect you to be so happy about that, Astra," Svetlana replied obliviously. "I mean, you and Max slept together every night!"

"Ghh- Hey! What the fuck, Svet!?" The Vulpix spat, bristling.

"The only way outside is the training field and the beach, but it's all surrounded. And Hope's Peak Guild is on an island, so there's no swimming to get away..." Pandora said.

"What about flying?" Murasaki pointed out.

"How long could you fly across an ocean for?" Zephyr shot back pointedly.

"Hey! I have tons of stamina." She puffed out her cheeks.

"Well...whoever's behind this, we're not going to stoop so low as to commit murder to leave! We aren't going to give them the satisfaction of seeing us kill." Riku stated, trying to rouse courage among the group. Some of the Pokémon nodded, but quite a few others looked less than impressed.

"Upupupupu, how can you be so sure?~" came a familiar, grating voice. At that moment, Monokuma appeared before them, chest puffed out proudly.

"H-How the fuck does he do that!?" Astra shrieked, falling backwards on her haunches.

"It's a secret, my dear Astra!" The Teddiursa tsked. "And don't worry about no murders occurring, because I have motives!~"

"M-Motives?" Vasily piped up, squirming in her chair. "Wh-What are m-motives?"

"Things that will urge you to kill each other!" He giggled. "Follow me!" With that, the teddy bear walked out of the room, beckoning them to follow. "If you don't, I may just have to punish you~"

Monokuma led them to a room with an intercom. Near it was a small recorder. The Teddiursa looked as if he could barely contain his devilish excitement.

"What is this room for?" Nico asked.

"It's the monitor room," Monokuma replied. "Where I make the announcements. Oh, and by the way, bedtime is at 10pm and daytime starts at 8am~! So you had better pay attention to the announcements~"

"Oh, and speaking of which..." Monokuma slammed a paw on the recorder. Immediately a shrill sound played over the intercom, not unlike a dog whistle. "No sleeping is allowed until a murder occurs~! This sound won't go away until you doooo."

"G-Gah! I c-can't take this!" Vasily promptly fainted.

"What? Are you going to sacrifice someone now?" Nutmeg leaned over her curiously.

"Hey! Give her space." Remy shooed her away, moving Vasily's body onto her shoulders. "I'm going to the infirmary."

"Doesn't that count as sleeping?" Crystal asked Monokuma, brow raised skeptically.

"Well, fainting make things more interesting, and it wasn't voluntary..." the bear pursed his lips. "Nah, it doesn't count. Now get out of here!" He waved a paw dismissively.

* * *

It had been three hours.  
Monokuma wasn't kidding when he said the sound wouldn't stop.

They had all been trying to make a plan, but it was impossible to think with that shrill, piercing sound constantly flowing through the air.

"Ugh, I'm getting antsy. A murder had better happen soon or else I'll take matters into my own hands!" Murasaki lashed her tail.

"Oh please, you couldn't kill anyone if you tried." Holly rolled her eyes.

"You wanna fucking test that theory, hot shit!?" Murasaki leaned forward, flexing her claws and flaring her wings.

"Why not? It'd get the game started." She chuckled darkly, smirking at the dragon's violent reaction.

"Murasaki, don't. She just wants to see you get angry." Izumi placed a hand on her arm.

"Ugh...whatever." The Flygon sat back down, but she was glaring daggers at the Lopunny.

"We need to...find a way to get out of here." Riku repeated. "Maybe we can't hear it outside?"

"Nope." Taiki shook his head. "I already checked. There are speakers out there so we can hear it."

"Dammit." Riku hissed under his breath. "The best thing we can do now then is eat and return to our rooms. Try not to fall asleep or anything—"

The intercom suddenly dinged, and Monokuma came on the intercom. "Ding dong, bing bong! It is now 10pm. At night is when the baddies come out to play, so are you _sure_ you want to stay out at night? You never know when a lowlife murderer might be lurking about, still cleansing themselves from the blood of their last victim..." he added ominously, before the intercom shut off.

"Ugh, we had better return to our rooms. Try not to fall asleep, anyone. There's no telling what he'll do if you do." Pandora warned, before bounding away.

"She's right. We should be very careful. Maybe we can stay in pairs." Izumi added. "There's safety in numbers, you know."

"Bah, fuck that! There's no way anyone could even think of touching me!" Murasaki cackled. "I'm going back to my room! None of you fuckers better even think of following me." With that she left, knocking over a rack with her tail, probably on purpose.

Max nodded nervously. "I-I'm leaving too. I don't want to be caught where I could get killed..." her scampered away, claws skittering on the floor as he went. Astra and Nico soon followed.

Crystal shrugged. "I'm leaving too. I sense that things will end badly for me should I choose to stay out any longer." Then she left as well.

"W-Wait! I don't want to b-be left alone here!" Dot called, following her quickly.

"I don't want to be left here either. No way am I going to get killed!" Svetlana ran out as well.

Eventually the only people left were Holly, Izumi and Riku.

"What are you going to do?" Holly asked suddenly.

"Wh-What?"

"Well, you're a detective, aren't you? If there is a murder, then you should be able to deduce who did it."

"Yeah...I guess...what about you, Izumi?" Riku turned to look at the Treecko.

"Well, I-I can calm people down. I could prevent mass hysteria should there be a murder..." Izumi stated. She seemed awfully calm despite the ear piercing sound and ban on sleep.

"Yeah, that could be useful." He offered a hopeful grin. Izumi gave a small, shy smile in return.

"In any case, we need to return to our rooms. There's no telling if someone could be plotting to murder us right now..." Holly muttered, before making her way out of the cafeteria.

Riku made his way to the dorms, finding a chibi picture of himself over one of the doors. He assumed it was his room.

"Huh. Cute." He pushed open the door and stepped inside. The room was spacious and comfortable looking, similar to a hotel room. The window was uncovered, but he doubted it was breakable.

Riku sat on his bed, keeping the lights on. The annoying sound still rang in his ears and he let out a grumble of annoyance, flattening them.

He noticed a bookshelf and made his way over to it, thumbing through the titles. Nothing interested him. He gave a sigh. Looks like there was nothing left to do but wait until morning...


End file.
